package org.lop.modules.utils;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.apache.commons.lang3.StringEscapeUtils;

/**
 * 封装各种格式的编码解码工具.
 * 
 * 1.Commons-Codec的 hex/base64编码
 * 
 * 2.自制的base62编码
 * 
 * 3.Commons-Lang的xml/html escape
 * 
 * 4.JDK提供的URLEncoder
 * 
 * @author 潘瑞峥
 * @date 2013-6-3
 */
public class EncodeUtils {

	private static final String DEFAULT_URL_ENCODING = "UTF-8";
	private static final char[] BASE62 = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".toCharArray();

	/**
	 * Hex编码.
	 */
	public static String encodeHex( byte[] input ) {
		return Hex.encodeHexString( input );
	}

	/**
	 * Hex解码.
	 */
	public static byte[] decodeHex( String input ) {
		try {
			return Hex.decodeHex( input.toCharArray() );
		} catch ( DecoderException e ) {
			throw ExceptionUtils.unchecked( e );
		}
	}

	/**
	 * Base64编码.
	 */
	public static String encodeBase64( byte[] input ) {
		return Base64.encodeBase64String( input );
	}

	/**
	 * Base64编码, URL安全(将Base64中的URL非法字符'+'和'/'转为'-'和'_', 见RFC3548).
	 */
	public static String encodeUrlSafeBase64( byte[] input ) {
		return Base64.encodeBase64URLSafeString( input );
	}

	/**
	 * Base64解码.
	 */
	public static byte[] decodeBase64( String input ) {
		return Base64.decodeBase64( input );
	}

	/**
	 * Base62编码.
	 */
	public static String encodeBase62( byte[] input ) {
		char[] chars = new char[input.length];
		for ( int i = 0; i < input.length; i++ ) {
			chars[ i ] = BASE62[ ( ( input[ i ] & 0xFF ) % BASE62.length ) ];
		}
		return new String( chars );
	}

	/**
	 * Html转码.
	 */
	public static String escapeHtml( String html ) {
		return StringEscapeUtils.escapeHtml4( html );
	}

	/**
	 * Html解码.
	 */
	public static String unescapeHtml( String htmlEscaped ) {
		return StringEscapeUtils.unescapeHtml4( htmlEscaped );
	}

	/**
	 * Xml转码.
	 */
	public static String escapeXml( String xml ) {
		return StringEscapeUtils.escapeXml( xml );
	}

	/**
	 * Xml解码.
	 */
	public static String unescapeXml( String xmlEscaped ) {
		return StringEscapeUtils.unescapeXml( xmlEscaped );
	}

	/**
	 * URL编码, Encode默认为UTF-8.
	 */
	public static String urlEncode( String part ) {
		try {
			return URLEncoder.encode( part, DEFAULT_URL_ENCODING );
		} catch ( UnsupportedEncodingException e ) {
			throw ExceptionUtils.unchecked( e );
		}
	}

	/**
	 * URL解码, Encode默认为UTF-8.
	 */
	public static String urlDecode( String part ) {

		try {
			return URLDecoder.decode( part, DEFAULT_URL_ENCODING );
		} catch ( UnsupportedEncodingException e ) {
			throw ExceptionUtils.unchecked( e );
		}
	}

}